Noisy Overdrives

[scott12180]

In the past I have commented that the Mitchell overdrive on my 236 Packard Phaeton was very noisy --- alot of

gear noise which got quite loud at times. I hated to drive with the top up !

I must make a public apology to Mitchell by saying that to my great surprise the noise was not from

the overdrive but the differential ! I never suspected that a Packard differential could make such a howlingly

loud gear noise and for the past four years just assumed it was the overdrive. But apparently someone had been into

my differntial before I acquired the car and did not know what they were doing. I removed the overdrive and re-installed the original driveshaft to make this diagnosis.

A friend had a rear axle from a 1927 which I swapped for my original, and with the overdrive I now have

a relativly quiet driveline. There is some slight gear noise which may still be from the overdrive

but it is nothing like it was.

Related to the thread on "High Speed Gears", it is very critical that the ring and pinion be installed

properly. If any one of a number of adjustments is not just right, the gears will be noisy. . . or fail.

--Scott

[bernardi]

I'm not familiar with Mitchel overdrives. Are they available for more modern cars - such as the 55-56 V8s? Someone several months ago commented on attempting to find or adapt an overdrive to go behind the Ultramatic. Does anyone know the status?